Entrance-exit route interlocking control apparatus



R. A. MCCANN ENTRANCE-EXIT ROUTE TNTERLOOKTNG CONTROL APPARATUS Sept. 1l, 1951 6 Sheets-Sheet l Filed Sept. 18, 1946 RT, SON SQL .NNN all@ NNN b AS1 uw NN SNJAR .A ummm/m lm wmlmwmfm INVENTOR Ronald ASTM @Smm O fm w mm wm T NNTMH. EPH f mwm, @L w armi Tm www fmmlm NL w mwm NN T.

mlSVV Nwl l @mma wr/mdw TALL; nu i HIS ATTORNEY Spt. 1l, 1951 R. A. MCCANN 'ENTRANCE-EXIT ROUTE INTERLOCKING CONTROL APPARATUS Filed Sept. 18, 1946 6 Sheets-Sheet 2 n). wm A m .BLMWBN SQ N m ly N www n nu WE@ 0 m ?11 i Fm f F m m S. NNN #HA @85 w A Mm Q a S@ .m IU R Fm@ E ,N GNN@ Aw @ws NMS +1 um. 1M@ E? JN .mwwlN WWHN www NNNN NN R. A. MOCANN 2,567,887

ENTRANCEEX1T ROUTE INTERLOCKING CONTROL APPARATUS Sept. 1l, 1951 6 Sheets-Sheet 3 iwfm QLNNSN HIS ATTORNEY NTWW m wkw @uw Filed Sept. 18, lf46 www ,A m NNN l WNN NWNJWS@ A@ QNNNM .r LIJ fm sept. 11, 1951 R. A. MCCANN ENTRANCE-EXIT ROUTE INTERLOCKING CONTROL APPARATUS 6 Sheets-Sheet 4 Filed Sept. 18, 1946 ANN wN A .11W H U1 l.

MSSS@ WWNNANMIYQ INVENTOR Ronald/ Yann BY ,A j

liv f ATTORNEY Sept. 11, 1951 R, A, MCCANN 2,567,887

IEZNTRANCEJEZXIT ROUTE INTERLOCKING CONTROL APPARATUS Filed Sept. 18, 1946 6 Sheets-Sheet 5 MN A n mm wwm @mj ,m Q A emu Si Y N EN b wwrw r n c Y@ wcm INVENTOR H012aZdA-M m12 HIS ATTORNEY MS M, 1mi Nmmm SE @www NN,

@www E u Y 4 I m @QESC WE wm @wwf @m www w Patented Sept. 11, 1951 UNITED STATES PATENT OFFICE,"

ENTRANCE-EXIT ROUTE INTELCKIG CoNrltoL APPARATUS Ronald A. vMcCann, Swissvale, Pa., assignor td The Union Switch and Signal Company, Swiss2 vale, Pa., a corporation of Pennsylvania Application September 18, 1946, Serial No. 697,704' 1s claims. (o1. 24e- 134) My-invention relates to interlocking control apparatus, and particularly to interlocking control apparatus in which manual control devices, such for example as push buttons, are provided in a track model or diagram at points corresponding to signal locations, for effecting operation of Athe track switches and a signal for each route by operation of the manual control devices for the two ends of the corresponding route. K A

an interlocking control system shown and described in Letters Patent-of the United States No.' 2,301,297 which was granted November 10, 1942 to Lloyd V. Lewis, for Railway Trac Controlling Apparatus the final route selector for any given route, las defined yby lines 33 to 36, in elusive, in the first column on page 5 of that patent, includes 'the exit stick relay for the given route and al1Y except the entrance stick relay of the preliminary route selector for the corresponding .route for the opposite direction o f traffic movements. For the route -I referred to in that patent, the nal route selector therefore does'not include relay 'IBNWS The preliminary route selector for route 4-I2 is defined by lines v1 to 5, inclusive, in the first co1- umn on page 4 of the patent.

Onejfeature lof my invention is the provision of means for including in the final route selector for each route allthe switch selector relays of the vpreliminary vroute selector for the opposite direction of trac movements. Because of this feature, no contacts of the exit stick relays are required for controlling the switch control relays..

' 'Another feature of my invention is the use of contacts of the exit stick relays without contacts of switch selector relays for effecting directional control of the route agreement relays which )correspond to the signal control relays shown in Fig. 1D of the patent referred to.

Because of these features, more economical use of relay contacts is provided, and hence fewer'relays are required in apparatus embodying my invention.

A further feature of my invention is the provision of through-route control for high speed through trailic movements, and intermediate route controlfor low speed diverging, switching, or call-on traic movements.

I shall describe one form of apparatus embodying my invention, and shall then point out the novel features thereof in claims.

,Y In the accompanying drawings, Figs. 1a to ik, inclusive, are diagrammatic views showing one form of apparatus embodying my invention, iri which Fig. 1a shows a layout of switches and signals in an interlocking plant, together with switch and signal operating circuitsand switch indication circuits; Fig. lb'shows a track model or diagram, and shows manual route control push buttons arranged in the track model at points corresponding to the signal locationsVand also shows individual levers for effecting separate operation of the switches; Figs. lc, 1d, le and 1f showroute selector circuits for the layout of Fig. la controlled by the manual control push buttonsof Fig. 1b; Fig. 'lg lshows the .circuit for controlling a through-route control relay.; Fig. lh shows route agreement relays controlled -by switch indication relays and by intermediate route stick relays PBS, and also by main exit stick relays XS,v but not by any of the switch selector relays; Fig. 1i shows control circuits for time locking relays; Fig. lf shows control cire' cuits for route locking relays; and Fig. llc shows control circuits for normal and reverse switch control relays controlled by switch selector ree lays without the exit stick relays, andalso shows control circuits for switch locking relays.

Similar reference'characters refer to similar parts in each of the views. I 'i In each of the views, the contacts operated by the various relays orother control devices are identified by numbers, each such number having a distinguishing prefix from-which it is separated by a dash when the associated contact is shown apartA from the relay or otherV de` Vice by which it is operated. The prefix for each` of these contact numbers comprises the reference character for the relay or other device by which the associated l:contact is operated.- For example, contact 2AH-'I0'L shown adjacent the symbol for signal 2Arin Fig. 1a, is identified by the number IIII separated by a dash fromvthe prefix 2AH which is'the reference character vfor relay ZAH by which this contact is operated.

Some contacts shown lin the drawings, but'which are included only in circuits which are not:

3 be arranged in normal and reverse positions to kform various routes. In order to simplify the drawing, each track, comprising two parallel series of track rails, is represented by a single line.

These tracks are divided by insulated joints I to form switch sections designated by the reference characters IT, 3T, and 5T in which switches I, 3 and 5, respectively, are located, and an approach section IGT. Each of these sections is provided with a track circuit including a suitable source of current such, for example, as a battery 9, connected across the rails adjacent one end of the section, and a track relay designated by the reference character ITR, 3TR, 5TR or IIITR, respectively, connected across the rails adjacent the opposite end of the section.

Traffic movements in opposite directions over the track layout shown are governed by signals, designated by the reference characters 2A, 2B, 4, 6, 8, I0, I2, IIIA and MB, respectively. These signals may be of any suitable design such, for example, Aas the semaphore or the searchlight type. I shall assume that traflic movements toward the right, as shown in the drawing, are eastbound, whereas those in the opposite direction are westbound.

Track repeater relays ITP, 3TP and 5TP, each having a slow pick-up and a slow release characteristic, are controlled by relays ITR, STR and 5TR, respectively, as shown, for example, for relay ITP.

Switches I, 3 and 5 are operable to their normal positions in which they are shown in the drawing, and to the opposite or reverse positions by mechanisms designated by the reference characters IM, 3M and 5M, respectively. Each of the mechanisms IM, 3M and 5M is in turn controlled by a. polarized switch control relay such, for example, as relay IW, as shown controlling .mechanism IM.

Relay IW is energized in the normal and the reverse direction by circuits controlled by a switch locking relay ILS in the energized condition, and by normal and reverse switch control relays designated by the reference characters INP and IRP, respectively.

A polarized switch indication relay IWP is controlled by relay IW and by contacts operated in conjunction with switch I.

The contacts which are operated in conjunction with switch I are designated by the reference characters i6, I l, |58, and I9, respectively. These contacts are operated similarly to contacts 23 and 24 shown in a Patent No. 1,970,111, granted August 14, 1934 to James J. Vanhorn for Railway Switch Controlling Apparatus. Contacts I6, I'I, I58, and I9 are operated in conjunction with switch I in such manner that contacts |58 and I9 are in the raised or front position, as shown in the drawing, at all times except when switch I is locked in its reverse position, and contacts I6 and I1 are in the raised or front position at all times except when switch I is locked in the normal position. Contacts I5 and I'I are in the lowered or vback position, as shown in the drawing, only when switch I is in the normal position, and contacts |58 and I9 are in the lowered or back position only when switch I is in the reverse position.

Normal and reverse switch repeater relays INWP and I RWP are controlled by a front contact and by normal and'reverse contacts, respectively, of relay IWP.

Normal and reverse switch indication relays INWK and IRWK are in turn controlled by relays INWP and IRWP, respectively, and by relays INP and IRP, respectively. Switch control, indication, and repeater relays shown in the drawing for switches 3 and 5 are controlled similarly to the corresponding relays, as just described, for switch I.

Through-route signal 2A is controlled by a circuit including a front contact of a signal relay ZAH. The circuit for energizing relay 2AH is shown in Fig. 1h. The other signals are controlled by corresponding route agreement relaysv as shown, for example, for signals 2B and 6.

Referring now to Fig. 1b, manual route control push buttons 2P, 4P, EP, 8P, II'IP, I2P and I4P are shown arranged in a track model or diagram adjacent representations of the corresponding signals. Individual switch levers IV, 3V and 5V are also shown for effecting separate operation of switches I, 3 and 5, respectively. Each of these switch levers has a normal position n, in which it is shown in the drawing, and also has a reverse position f to the left, and a reverse `position r to the right.

Referring next to Figs. lc, ld, le 'and 1f, circuits are here shown for controlling intermediate route stick relays each of which is designated by a reference character comprising a number corresponding to that of an associatedsignal, followed by the letters PBS; for controlling main exit stick relays each of which is designated 'by the reference character XS preceded by a corresponding signal number; for controlling switch selector relays each of which is designated by a reference character comprising the letter N vor vR for normal or reverse switch position, respectively, followed by the letter E or W for eastbound or westbound route, respectively, and preceded by a number I, 3 or 5 for switch I, 3 or 5, respectively; and for controlling auxiliary exit stick relays designated by the reference character XR preceded by a numeral corresponding to that of an associated signal.

The circuits shown in Figs. lc, 1d, 1e and lf are controlled by the manualroute control push buttons shown in Fig. 1b, each of which is designated by the reference character P preceded by the reference number for vthe signal for the corresponding route Yend. Each of these push buty tons operates a circuit controller which is of the push-pull type such, for example, as shown in Letters Patent of the vUnited States No. 2,295,301 granted September 8, 1942 to William E. Smith for Circuit Controllers. Each of these control- 1ers is biased to a mid stroke position, and has a normally open contact and a normally closed contact such, for example, as contacts 43 and 52, respectively, of controller 2P shown at the left-hand end of Fig. lc. Contact 43 .becomes closed when .button 2P is pushed in, and contact 52 becomes opened when button 2P is pulled out.

The circuits are so designed that operation of push buttons 2P and I4P will arrange `a through route including switches I, 3 and 5 in their normal positions, and will effect the clearing of signal 2A for directing traffic movements over this route. A type of signaling is used here, in which the intermediate signals 6 and I0 do not affect through traffic movements governed by signal 2A, and therefore signals 6 and I0 are left in the stop position while a through trailic movement-governed by signal 2A is being made past these signals.

For arranging any other route or providing for a Gall-on traic movement to be governed by tacts of the exit stick relays.

i signals 2B, 6 and-Ill over the routeon which trafiic movements are normally governed ybyvsignal 2A, all the push buttons shown in the representation of such route in Fig. 1by must be operated, and the intermediate signals as well as the entering signal for such route will then be cleared. For example, in order to authorize a call-on trafc movement to be made over the route governed by signals 2B, 6 and I0, push buttons 2P and 6P must be operated for the rst intermediate route from signal 2B to signal 6, then push buttons 6P and ISP must be operated for the second intermediate route from signal Ii` to signal IB, and finally buttons IDP and I4P must be operated for the third intermediate route from signal III to signal I4.v Signals 2B, 6 and III will then be cleared. Similarly, in order to arrange any of the diverging routes shown, such, for example, as the route which includes switch 5 re'- versed, push buttons 2P and 6P must be -operated, then 6P and IUP, and finally IIJP and |2P must be operated. After switch 5 has been reversed, signals 2B, 6 and I0 will be cleared.

In Fig. lg, afcircuit isshown for controlling a through route control relay BZ. n

In Fig. 1h, circuits are shown for controlling route agreement relays 2AR, 2BR, 4R, 6R, BR, IGR, I2R and I4R. These circuits include contacts of the normal and reverse switch indication relays, and of the intermediate route stick relays, and also of' the main exit stick relays, but do not include any contacts of the switch selector relays. A circuit for controlling signal relay 2AH is also shown in Fig. lh.

In Fig. 1i, control circuits are shown for time :2

locking stick relays ZAAS, 2BAS and BAS, and for the associated time element devices 2ATE, ZBTE and ETE, respectively. The time element devices may be of any suitable design such, for example, as the thermal type. Control circuits for time locking stick relays 4AS, BAS, IIJAS, IZAS and I4AS are similar to the circuits shown in Fig. 1i.

In Fig. 19, control circuits are shown for route locking stick relays IES, 3ES, SES and 3WS.

Referring finally to Fig. lk, the normal and reverse switch control relays are shown controlled by the switch selector relays without con- Circuits are also shown for controlling switch locking relays ILS, 3LS and 5LS.

Having described, in general, the arrangement and control of the apparatus shown by the accompanying drawings, I shall now describe, in detail, its operation.

As shown by the drawings, all parts are in the normal condition, that is, switches I, 3 and 5 are in their normal position; all signals are indicating stop; all track sections are unoccupied, and hence the track relays and track repeater relays are energizedyeach of the levers IV, 3V and 5V is in its normal position n; the controllers operable by push buttons 2P, 4P 6P, 8P, IDP, I2P and I4P are in their biased mid stroke position; relays INWP, SNWP, ENWP, the time and route locking relays shown in Figs. lz' and 17', respectively, and relays ILS, 3LS and 5LS are energized; relays IWP, 3WP and SWP are energized by current of normal polarity; and relays IW,V 3W, 5W, IRWP, SRWP, SRVVP, INWK, 3NWK, 5NWK, IRWK, 3RWK, SRWK, SPBS, IIlPBS,` GXR, IIBXR, the route selector relays including the switch selector relays and the exit stick relays shown in Figs. lc, 1d, le and lf, relays- SZ and 2 AH, the route agreement relaysshown in Fig. 1h, and the normal and reverse switch control relays shown in Fig. llc are deenergized.

The circuit by which relay ITP is energized passes from terminal B of a suitable source of current, through contact II of relay ITR, and Winding of relay ITP to terminal O of the same source of current. Contact VVV-I3 is closed in the left-hand position in a circuit for energizing mechanism IM, this circuit passing from terminal B, through contact IW-I3 in the lefthand position, and mechanism IM to terminal O. Relay IWP is energized by current of normal po larity in a circuit passing from terminal B,'

through contact I5 of relay IW closed in the left-hand, or normal, position, contact I6 operated in conjunction with mechanism IM, winding of relay IWP, and contact II operated in conjunction with mechanism IM to terminal O. The circuit by which relay INWP is energized passes from terminal B, through contact 20 of relay IWP, contact 2| of relay IWP closed in the left-hand position, and the winding of relay INWP to terminal O.

Relay ZAAS, shown in Fig. lz', is energized by a stick circuit passing from terminal B, through contacts ZAR-22 and 2AH-23, front point of contact 24 of relay ZAAS, and the winding of relay ZAAS to terminal O. Relay ZBAS is energized by a stick circuit passing from terminal B, through contact 2BR-22, front. point of contact 24 of relay ZBAS, and the winding of. relay 2BAS to terminal O. Relay SAS is energized by a stick circuit which is similar to the one just traced for relay ZBAS.

Both a pick-up and a stick circuit are closed for energizing relay 3WS shown in Fig. 17, the pick-up circuit passing from lterminal B, through contacts 25, 26 and 21 of relays MAS, I2AS and BAS, respectively, contact 5TH-28, contact STR-3S, and the winding of relay 3WS to ter-` minal O. The stick circuit passes from terminal B, through contacts 25, 26 and 21 of relays I4AS, I2AS and SAS, respectively, contact 3| of relay 3WS, and the winding of relay 3WS to terminal O. Both a pick-up and a stick circuit are also closed for energizing each of the other route locking relays, the pick-up circuit for relay 5ES passing from terminal B, through contact 25 of relay IOAS, contact 3ES-32, contact 5TH- 33, and the winding of relay 5ES to terminal O. The stick circuit is the same as the pick-up circuit just traced except that it includes contact 34 of relay 5ES instead of contact STR-33. The pickup and stick circuits for relays IES and SES are similar to the circuits just traced for relay SES.

Both a pick-up and a stick circuit are closed for energizing relay ILS shown in Fig. llc, the

pick-up circuit passing from terminal B, throughv contacts 2AAS-35, 2BAS-36, 4AS-3, 3WS-38 and I TR--39, winding of relay ILS, and contact IV-40 to terminal O. The stick circuit for relay ILS is the same as the pick-up circuit just traced except that it includes contact 4I of relay ILS instead of contact lIII-4I). Relays SLS and SLS are energized by circuits which are similar to the circuits just traced for relay ILS.

I shall assume that a leverman desires to arrange the through route governed by signal 2A. He will, therefore, depress push button 2P, closing a circuit for energizing relay INE shown in Fig. lc, this circuit passing from terminal B, through contact ITR-42, contact 43 operated by button 2P, back point of contact IEW-44. back point of contact INW-45, back point of contact 2XS-45, Winding `of relay INE, and contacts IRW-4'I and IRWK-IIS to terminal O. Relay INE, upon becoming energized, closes its own stick circuit passing from terminal B, through contact VTR-42, contact 52 of button 2P, contact 53 of relay INE, back point of contact 2XS-5, Winding of relay INE, and con"- tacts IRW-l and IRWK-LIB to terminal O.

A circuit for energizing relay IRE is also closed by operation of push button 2P, this circuit passing from terminal B, through ccntact VIR-42, contact 43 of relay 2P, back point o contact IRW--, back point of contact DiS-49, winding of relay IRE, and contacts INW-59 and INWK5I to terminal O. A stick circuit is also closed for energizing relay IRE when relay IRE becomes energized, this circuit passing from terminal B, through contact ITR-42, contact 52 of push button 2P, contact 54 of relay IRE, back point of contact DiS-49, winding of relay IRE, and contacts INW-5tl and INWK-BI to terminal O.

Relay INE, upon becoming energized, closes a circuit for energizing relay BZ shown in Fig. 1g, this circuit passing from terminal B, through contacts ITB-55, STR-56, ETR-51, ISTR- 53, INE-59, 6XS-IL and the winding of relay GZ to terminal O.

Relay SZ, upon becoming energized, completes a circuit for energizing relay SNE, Fig. le, this circuit passing from terminal B, through the front point of Contact 6Z6I, winding of relay SNE, and contacts SRW-BZ and SRWK-' to terminal O. Relay GZ, upon becoming energized, also completes a circuit for energizing relay SNE, Fig. 1f, this circuit passing from terminal B, through the front point of contact tZ--i, winding of relay ENE, and contacts SRW- and ERWK-BE to terminal O.

The leverman will then depress push button HIP, Fig. 1f, thereby completing a pick-up circuit for energizing relay IXS, this circuit passing from terminal B, through contact STR-El, contact 68 of button IQP, front point of contact SNE-B9, back point of contact NW, winding of relay IAXS, and contact IllAS-lI to terminal O. Relay NXS, upon becoming energized, completes its stick circuit passing from terminal B, through Contact I2 of relay NXS, Contact ENE-13, winding of relay IilXS, and contact IIIAS-TI to terminal O.

Relay IAXS, upon becoming energized, completes a pick-up circuit for energizing relay ENW, this circuit passing from terminal B, through Contact NE-N, front point of contact NXS-15, winding of relay ENW, and contacts ERW- and SRWK-SS to terminal O. Relay 5NW, upon becoming energized, completes its own stick circuit passing from terminal B, through contact ETR-6l, contact 1E or push button I 4P, contact 'I'I of relay ENW, winding of relay ENW, and contacts RW- and :":RWK- 66 to terminal O.

With relay ENW energized, a second stick circuit is completed for relay MXS, which is the same as the stick circuit previously traced for this relay except that it includes the front point of contact 5NW-'Ill instead of contact ENE- 13.

Relay ENW, upon becoming energized, completes a circuit for energizing relay 3NW, this circuit passing from terminal B, through contact 5NW-'I3, contact IOPBS-19, winding of relay 3NW, and contacts SRW-SZ and 3RWK-63 to terminal Ov. Relay BNW, upon becoming energized, in turn completes a circuit for energizing relay INW, this circuit passing from terminal B, through contacts SNW-S and 6PBS-8I, winding of relay INW, and contacts IRW-II'I andl IRWK-48 to terminal O. Relay INW, upon becoming energized, opens its contact INW- in the pick-up and stick circuits for relay IRE, thereby causing relay IRE to become deenergized.

It follows that, in apparatus embodying vmy invention, the first route control push button operated f-or a route marks the entrance end of the route, and effects the energization of a preliminary route selector which comprises a first switch selector relay for each switch in the route in the position required for the route. For example, for the through route governed by signal 2A, the preliminary route selector comprises the rst switch selector relays INE, SNE and SNE. Subsequent operation of the route control push button for the opposite or exit end of the route effects the energization of a nal route selector which comprises an exit stick relay for the route and a second switch selector relay for each switch in the route in the position required for the route. For example, for the through route governed by signal 2A, the nal route selector comprises the exit stick relay IAXS and all the second switch selector relays ENW, 3NW and INW.

For the opposite direction of tramc movements over the same route, the preliminary route selector comprises the second switch selector relays ENW, SNW and INW, and the nal route selector comprises the exit stick relay 2XS and all the first switch selector relays INE, SNE and SNE.

Nt will be seen, therefore, that the nnal route selector for each route comprises all the switch selector relays of the preliminary route selector for the opposite direction of tralic movements.

With relays INE and INW energized, a circuit shown in Fig. 1k is completed for energizing relay INP, this circuitk passing from terminal B, through the winding of relay INP, and contacts IRP- 82, INE-83, and INW-84 to terminal O. Relays 3NP and SNP become energized by similar circuits also shown in Fig. llc.

Relay INP, upon becoming energized, completes a circuit for energizing relay IW by current of normal polarity as shown in Fig. 1a, this circuit passing from terminal B, through the front point of contact INP-454, contacts ILS- |55, winding of relay IW, contact ILS-ISS, and the back point of contact IRP- |51 to terminal O. Since the contacts of relay IW are already in the normal position, they will not change when relay IW becomes energized by the circuit just traced. Relays IWP and INWP will therefore remain energized by their circuits previously traced.

Relay INWK, however, now becomes energized by a circuit passing from terminal B, through contact 85 of relay INWP, contact INP-86, and the winding of relay INWK to terminal O. With relays 3NP and SNP also energized, relays SNWK and ENWK will become energized by circuits similar to those just traced for relay INWK.

A route agreement relay ZAR, shown in Fig. 1h, will now become energized by a circuit passing from terminal B, through the front point of contact NXS-81, contact 5NWK-88, back points of contacts IIlPBS-89 and IOXS-BI), contact 3NWK-9I, back points of contacts SPBS-SZ and GKS-93, contact INWK-94, back points of contacts 2XS-95 and SKS-96, contacts 5NWK-9'I, SNWK-SB and INWK-QS, and the winding of relay ZAR to terminal O. Relay 2AR, upon becoming energized, opens its contact ZAR-22 in the stick circuit traced for 9 relay ZAAS in Fig. lz', causing relay 2AAS to become deenergized.

Upon deenergization of relay 2AAS, its contact 2AAS--35 in the circuits traced in Fig. 1k for relay ILS will become opened, thereby deenergizing relay ILS. The circuits for relay IES, shown in Fig. li, will also become .deenergized because of the Vopening of contact 2AAS;32. Relay VSES will then be deenergized because contact IES-32 will be opened, and relay 5ES will bedeenergized vbecause contact SES-32 will be opened. The deenergization of relay SES also opens its contact SES- 3l in the circuits for relay 3LS shown in Fig. 1k, and hence relay SLS will be deenergized. Likewise, deenergization of relay EES opens contact SES-3.8 in the circuits shown for relay SLS, 'causing relay 5LS to also be deenergized.

With relay ILS deenergized, a normal retaining circuit for relay INP becomes closed, passing from terminal B, thrcugh the winding of relay INP, contact IRP-82, contact IWP-Ill closed inthe left-hand position, and contact ILS-IBI to terminal O. Relays 3LS and ELS, upon becoming deenergized as described, complete normal retaining circuits for relays 3NP and SNP which are similar to the circuit just traced for relay INP vthrough contact ILS-I I fjfWith relay ZAR energized, relay ZAH, shown in Fig. lh, becomes energized by a circuit passing from terminal B, through contact IG2 of relay fAR, contacts ITR-|03, 3TR-ID4, STR-H35 and IDTR-IUB, and the winding of relay 2AH to terminal O. Signal 2A will now be cleared by al circuit passing from terminal B, through contact 2AH-I0'I, and the mechanism of signal 2A to terminal O. Signal 2A, upon becoming thus operated, will authorize a through traflic move ment past signals 6 and I0 in their stop position.

When a train passes signalZA, relay ITR will become deenergized, and henceits contact ITR- .ID3 will, open the circuit previously traced for relay ZAH. causing this relay to become' deenerg'i'zed and thereby causing the arm of signal 2A to'return to the stop position. Relay INE will also become deenergized because contact ITR- 42 will open.

The circuit for relay BZ will also be open at contact ITR-55. With relay SZ deenergized, the circuit previously traced for relay 3NE will be open at contact `lZ- I and the circuit previously traced for relay SNE will be open at the front point of contact (i2-64, and hence relays SNE and ENE will be deenergized. With relay ENE deenergized, the pick-up circuit traced for relay NW will be opened at contact ENE-14, but relay 5NW will remain energized by its stick circuit until the train enters section 5T and thereby deenergizes relay 5TR, causing contact STR-61 to become opened. With relay 5NW as well as relay SNE then deenergized, `the stick circuits previously traced for relay IIIXS will be opened at contacts SNE-13 and 5NW'I0, respectively, causing relay IIIXS to be deenergized. With relay IIIXS deenergized, contact NXS- 81 will open the circuit previously traced for relay 2AR. Relay vBNW will now be deenergized because of the opening of contact 5NW-'I8, and relay VINW Will then be deenergized by the opening of contact 3NW--8Il- When the train enters section I T, deenergizing relay ITR, relay 2AAS becomes' energized by a pick-up circuit passing from terminal B, through contacts 2AR-22, 2AH-23 and ITR-|08, and vthe winding of relay 2AAS to terminal O. Then when the train leaves section IT,'relay IES will become energized by its pick-up circuit. Sim- 10 ilarly, When the train leaves section 3T, relay 3ES will become energized by its pick-up circuit. Relays ILS and 3LS will now be energized by their pick-up circuits previously traced.

I shall now assume that, with section 5T occupied, the leverman decides to provide for a callon trac movement over. the route governed by signals 2B, -6 and II). He will, therefore, depress push button 2P as before, causing the pick-up and stick .circuits to close for relays INE and IRE as previously described. Through-route control relay GZ will not now become energized, however, since its circuit is open at contact STR- 51.

Relay BXR, shown in Fig. 1d, will, however, become energized by a circuit passing from termin-al B, through Contact INE-|09, back point of contact IIO of relay GXS, winding of relay iISXR, and contacts 3NW--I II and 3RW-I I2 to terminal O. Relay BXR, upon becoming energized, will complete its stick circuit which is the same as the pick-up circuit just traced except that it includes contact II3 of relay SXR instead of contacts SNW-I II and 3RW-I I2.

The leverman will now depress push button 6P to eiect energization of relay GXS by its pick-up circuit passing from terminal B, through contact INE-IDS, contact II4 of the'circuit controller operated by push button ISP, winding of relay GXS, and contacts 3NW--I I5 and 3RW-I I6 to terminal O. Relay BXS, upon becoming energized, completes its stick circuit which is the same as the pick-up circuit just traced except that it includes the front point of contact IIII of relay GXS instead of contact II4 of controller 6P and includes contact GXS-I I'I instead of oontacts 3NW-I I5 and 3RW-I I6.

As long as push button 6P remains depressed, relay BXR will continue energized by a second stick circuit after relay GXS picks up, the second stick circuit passing from terminalB, through contact INE-IGS, front 'point of contact BXB.- I I8, contact I I9 of push button 6P, front point of contact SKR-|20, winding of relay BKR., and contact II3 of relay BXR to terminal O.

With relay EXS energized, relay INW becomes energized by a second` pick-up circuit passing from terminal B, through contact 6XS- I2I, winding of relay INW, vand contacts IRW-M and IRWK-48 to terminal O. Relay IRE then becomesdeenergized by the opening of contact INW-5I). u i

In order to effect energization of relay GPBS, the leverman will permit button 6B to return to the normal positionto open, at contact IIS of button 6P, the second stick circuit traced Afor relaySXR, causing relay IXR to become deenergized. He will then again depress push button 6P, causing relay GPBS to become energized by a pick-up circuit passing from terminal B, through contact STR-|22, back point of contact 6XR I I8, contact I I9 of push button 6P, back point of contact 6XR-I20, winding of relay SPBS, and contacts 3NW-I I5 and 3RW-I I6, connected in multiple with contact BXS-I I'I, to terminal O. Relay GPBS, uponbecoming energized, will complete its stick circuit passing from terminal B, through contact 3TR-I22, contact |23 of push button 6P, contact |24 of relay GPBS, and con tact 6PBS-I25 to terminal O.

With relay BPBS energized,`relay SNE Fig. 1e, will now be energized by a second circuit passing from terminal B, through contact BPBS-IZB, winding of relay 3NE, and contacts 3RW-'62 `and 3RWK-63 to terminal O. Relay 3RE will now also be energized by a circuit passing from ter--v i i minal B, through the front point of contact SPBSTIZF, winding of` relay SRE, and contacts 3NW-.l28 and SNWK-.IZS to terminal O. With relay 3NE energized, relay lXR will become energized by a circuit passing from terminal B, through contact SNE-13B, back point of contact `lI-ll of relay IBXS, winding of relay IDXR, and contacts 5NW..I32 and 5RW.-l33 to terminal O. Relay IXR, upon becoming energized, completes its own stick circuit which is the same as the pickmp circuit just traced except that it includes contact i3d of relay IUXR instead of contacts 5NW-.32 and 5RW.I33.

rThe leverman will now depress push button IBF for energizing relay IUXS by its pick-up cir cuits passing from terminal B, through contact 3NE-lv3L contact |35 of push button lill?, windingl of relay IUXS, and contacts 5NW-l36 and BBW- E37 to terminal O. Relay IUXS, upon becoming energized, completes its stick circuit. passing from terminal B, through contact SNE-456i, front point of contact 13| of relay lXS, winding of relay IGXS, and contact liEXSf-.i to terminal O.

While push button IEJP remains depressed, a second stick circuit is closed for relay IQXR, passing lfrom terminal B, through contact SNE-ii, front point of contact lXR-l39, contact Id of push button HBP, front point of Contact lXR-c-IM, winding of relay IIJXR, and contact E34 of relay IIJXR to terminal O.

Relay HlXS, upon becoming energized, completes a second circuit for energizing relay SNW, passing from terminal B, through contact NXS-|42, winding of relay SNW, and contacts RW-SZ and 3RWK-63 to terminal O. Relay 3NW, upon becoming energized, opens its contact 3NW-l28 in the circuit previously traced for relay- 3RE, causing relay 3BE to become deenerg-ized. With relay 3NW energized, a third circuit becomes closed iorenergizing relay SNE, this circuit passing from terminal B, through con tacts GAS-143, INE-...444, SNW-MS, back point of contact 621-51, winding of relay 3NE, and conf tacts 3RW--B2 and SRWK-BS to terminal O.

In' order to effect energization of relay WEBS, the leverman will return button IlP to its normal position to deenergize relay IOXR, and will then again depress push button IOP for completing pick-up and stick circuits for relay IEJPBS which L are similar to the circuits previously traced for relay SPBS. Relay ENE will then become energized by a second circuit, passing from terminal B, through contact |PBS--l50, winding of relay SNE, and contacts RW-65 and BRWK-S'n to terminal O. Relay SRE will also be energized by a circuit passing from terminal B, through the front point of contact IGPBS-IEI, winding of relay BRE, and contacts 5NW-l52 and 5NWK-i53 to' terminal O.

The leverman will now depress push button MP, thereby completing a pick-up circuit for relay I4XS which is the same as the pick-up cir. cuit prev-iously traced forl this relay except that it includes contact ETP- |46 instead of contact STR- 67. Relay 5NW will then become energized as previously described. Relay ENW, upon becoming energized, opens its contact 5NW-l52, thereby deenergizing relay ERE.

With relay GXS energized, route agreement relay ZBR, shown in Eig, 1h, will be energized by a circuit passing from terminal B, through the front point of contact GKS-9 3, contact INWK- Sfh back point of contact 2XS-95, front point of contact GKS-96, and winding of relay 2BR to terminal O. With relays IXS' 'and 'SPBS energized, route agreement relay 6R is energized by a circuit passing from terminal B, through the front point of contact IilXS-SIL contact SNWK-Sl front point of lcontact SPBS-SZ, and the winding of relay 6R to terminal O. With relays iPiXS and IUPBS energized, route agreement relay IOR will be energized by a circuit vpassing from terminal B, through the front point of contact NXS-.81, contact 5NWK88, front point of contact IBPBS-BS, and the winding of relay ISR to terminal O.

It follows that, in order to arrange the through route governed by signal 2A, each of the push buttons 2P and Uil? is depresed once, and that in order to arrange for a call-on trac movement over this route, each o the push buttons 5P and HlP is depressed twice in addition to the single operation of push buttons 2l? and MP. The following tabulation Shows the operation of the push buttons for arranging this route for through traffic movements and for call-on traic movements, and also shows the operation of the push buttons f or arranging the other possible eastbound. routes- Route Operation of Push Buttons From the foregoing description of the operation of the apparatus for arranging a through route governed by signal 2A and including switches i, 3 and 5 in theirnormal positions, and for arranging for a call-on traic movement over this route vgoverned by signals 2B, 6 and I0, it is believed that the operation of the apparatus for any other possible traffic movement can be readily traced. v

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

l. In interlocking control apparatus including a manual control device for each route end of a plurality of interconnected railway track routes; in which energization of a preliminary route se-A lector for each route including a switch selector relay for each switch of the route for the position in which the switch is included in the route is effected by operation of the manual control device for the entrance end of the route, in which energization of an exit stick relay for each route is eiected'byoperation ofthe manual control device for the exit end of the route while the preliminary route selector for the same route is energized, the combination comprising, a nal route selector for each route each including a second switch sclector relay for each switch ofthe route for the position in which the switch is included in the route, a, pick-up circuit for the second switch se-V lector relay for the last switch in each route controlled by a front contact of the exit stick relay for that route in series with a front contact of the first switch selector relay for that switch, and a stick circuit for the second switch selector relay for the last switch in each route controlled by the manual control device for the exit end of the route in its normal position.

2. .n interlocking control apparatus including a manual control device for each route end of -a plurality of interconnected railway track routes, in which energization of a preliminary 'route selector for each route including .a switch selector relay for each switch of the route for the position in which the switch is included in the route is eiected by operation of the manual controlv device for the entrance end of the route, in which energization of an exit stick relay for each route is eiected by operation of the manual control device for the exit end of the route while the preliminary route selector for the same route is energized, the combination comprising, a nal route selector for each route each including a second switch selector relay for each switch of the route for the position in which the switch is included in the` route, an energizing circuit for the second switch selector relay for the last switch in each route controlled by a front contact of the avmanual control device for each route end of a l plurality of interconnected railway track routes, in which energization of a preliminary route selector for each route including a switch selector relay for each switch of the route for the position in which the switch is included in the route is eiected by operation of the manual control device for the entrance end of the route, in which energization of an exitstick relay for each route is effected by operation of the manual control device for the exit end of the route while the preliminary route selector for the same route is energized, the combination comprising, a final route selector foreach route each including a second switch selector relay for each switch of the route for the position in which the switch is included in the route, an energizing circuit for the second switch selector relay for the last switch in each route controlled by a front contact of the exit stick relay for that route, and two stick circuits for each exit stick relay one of which is controlled by a front contact of the rst switch selector relay `for a switch in its route and the otherA of which is controlled by a front contact of the second switch selector relay for the same switch in its route.

4. In interlocking control apparatus including t afmanual control device for each route end' of a plurality of interconnected railway track routes, in which energization of a preliminary route selector for each route including a switch selector relay for each switchof the route for the position in which the switch is included in the route is effected by operation of the manual control device for the entrance end of the route, in which energization of an exit stick relay for each route is eiected by operation of the manual control device for the exit end of the route while the preliminary route selector for the same route is energized, the combination comprising, a nal route selector for each route each including a second switch selectorrelay for each switch of the route for theposition in which thev switch is included in the route, means responsive to energization of the exit stick relay for each route for effecting energization of the second switch selector relay for each switch of the same route,

i4 and two stick Acircuits for each exit 'stick relay one'of which is controlledby a front contact of the rst switch selector relay for a switch in its route and the other of which is controlled by a front contact lofthe second switch selector relay for the same switch in its route.

5. In interlocking control apparatus including a manual control device foreach route end of a plurality of interconnected railway track routes, in which energization of a preliminary routeselector for each route including a switch selector relay for each switch of the route for the position in which the switch is included in the route is effected by operation of the manual control device for the entrance end of the route, in .which energization of an exit stick relay for each route is effected by operation of the manual control device for the exit end .of the route while the preliminary route selector for the same route is energized, the combination comprising, a final routeselector for each route each including a secondswitch selector relay for each switch 0f the route for the position in which the switch is included vrin theiroute, means responsive to energization of the exit stick relay for each route for effecting energization of the second switch selector relay for each switch of the same route, and normal and reverse control means controlled by the first and second switch selector vrelays for each switch for effecting operations to normal and reverse positions respectively required forlthe corresponding. switch for each direction of tradi@ movements. 6. In interlocking control apparatus including a manual control device for each route end of a plurality of interconnected railway track routes, in which energization of a preliminary route selector for each route including a switch selector relay for each switch of the route for the .position in which the switch is included in the route is eiected by operation of the manual control device for the entrance end of the route, in which energization of an exit stick relay for each route is effected by operation of the manual control device for the exit end of the route while the preliminary route'selector for the same route is energized, the combination comprising, a nal route selector for each route each including a second switch selector relay for each switch of the route for the position in which the switch is kincluded in the route, means responsive to energization. of the exit stick relay for each route for effecting energization of the second switch selector relay for each switch of the same route, and a normal and a reverse control relay for each switch each controlled by the corresponding first andsecond switch selector relays for effecting all operations to normal and reverse positions respectively required for the corresponding switch for each direction of v traic movements.

'7. In interlocking control apparatus including a manual control device for each route end of a plurality of interconnected railway track routes, in which energization of a preliminary route selector for each route including a switch selector relay for each switch of the route for the position in which the switch is included in the route is effected by operation of the manual control device for the entrance end of the route, in which energization of an exit stick relay for each route is effected by operation of the manual control device for the exit end of the route while the preliminary route selector for the same route is energized, the combination comprising, a final route selector for each route each including a second switch selector relay for each switch of the route for the position in which the switch is included in the route, means responsive to energization of the exit stick relay for each route for eilecting energization of the second switch selector relay for each switch of the same route, and a normal and a reverse control relay for each switch each having a pick-up circuit controlled by iront contacts of the rst and second switch selector relays for the normal or reverse position respectively of its switch for each direction of traiic movements, and each having a stick circuit controlled by a back contact of a locking relay for its switch.

8. In interlocking control apparatus including a manual control device for each route end of a plurality of interconnected railway track routes, in which energization of a preliminary route selector for each route including a switch selector relay for each switch of the route for the position, in which the switch is included in the route is effected by operation of the manual control device for the entrance end of the route, in which energization of an exit stick relay for each route is eiected by operation of the. manual control device for the. exit end of the route while the preliminary route selector for the same route is energized, the combination comprising, a final route selector for each route each including a second switch selector relay for each switch of the route for the position in which the switch is included in the route, means responsive to energizaton of the exit stick relay for each route for effecting energization of the second switch selector relay for each switch of the same route, a normal and a reverse control relay for each switch each controlled by the corresponding first and second switch selector relays for the normal or reverse position respectively for its switch, for each direction or traiiic movements a normal and a reverse repeater relay for each switch each energized according as the corresponding switch is controlled to occupy the normal or the reverse position respectively, a normal indication relay for each switch controlled by the normal control and repeater relays for its switch, and a reverse indication relay for each switch controlled by the reverse control and repeater relays for its switch.

9. In interlocking control apparatus including a manual control device for each route end of a plurality of interconnected railway track routes, in which energization of a preliminary route selector for each route including a switch selector relay for each switch of the route for the position in which the switch is included in the route is effected by operation of the manual con--v trol device lfor the entrance end of the route, in which energization of an exit, stick relay for eac-h route is effected by operation of thev manual control device for the exist end of the route while the preliminary route selector for the same route is energized, the combination compris-ing, a nngl route selector for each route each including a second switch selector relay foreach switch of the route for the position in which the switch is included in the route, means responsive toV ener-5 gization ofv the exit stick relay for each route for eiiecting energization of the second switch selector relay for each switch of the same route, two stick circuits for each exit stick relay one of which is controlled by a front contact of the first switch selector relay for a switch in its route and the other of which is controlled by a front contact of the second switch selector relay for the same switch in its route, a plurality of route agreement relays one for each route, and a control circuit for each route agreement relay controlled by a front contact of the exit stick relay for its route and by a back contact of the exit stick relay for the corresponding route for the opposite direction of trafc movements.

l0. In interlocking control apparatus including a manual control device for each route end of a plurality of interconnected railway track routes, in which energization of a preliminary route selector for each route including a switch selector relay for each switch of the route for the position in which the switch is included in the route is effected by operation of 'the manual control device for the entrance end of the route, in which energization of an exit stick relay for each route is effected by operation or" the manual control device for the exit end of the route while the preliminary route selector for the same route is energized, the combination comprising, a iinal route selector for each route each including a second switch selector relay for each switch of the route for the position in which the switch is included in the route, means responsive to energization of the exit stick relay for each route for eecting energization of the second switch selector relay for each switch of the same route, and means responsive to energization of the rst and second switch selector relays for each switch for each route for effecting operation of the oor-1 responding switch to the position required for the corresponding route for each direction of traiic movements.

l1. In interlockingv control apparatus including a manual control device for each route end of a plurality ofv interconnected railway track routes, in which a, through traffic signal is provided for governing traflic movements over a through route `including a plurality of intermediate routes in series while the signals for said intermediate routes are indicating stop, in which energiza-tion of a preliminary route selector for each route including a switch selector relay for each switch of the route is eiected by operation of the manual control device for the entrance end of the route,l in which energization of an exit stick relay and a: nal route selector for each route including a second switch selector relay for each switch of the route is effected by operation of the manual control device for the exit end of the route while the preliminary route selector for the same route is energized, the combination comprising, a through traic relay controlled by a front contact of the first switch selector relay for the rst switch and by a back contact of the exit stick relay for the rst, intermediate route in said series if all of. said intermediate routes are unoccupied, means controlled byy said through traflic relay for energizing the rest of said rst switch selector relays for said through route, and means controlled by operation of the manual control device for. the exit end of the last intermediate route in said series for effecting energization of a nal route selector including all of said second switch selector relays for said through route and for clearing said through traffic signal if all of said first and second switch selector relays for said-through route have become energized.

l2. In interlocking control apparatus including a manual control device for each route end of a plurality of interconnected railway track routes, in which a through traine signal is provided for governing traine movements over a through route. includingA a plurality of intermediate routes in 17 seriesv While thev signals for said intermediate routes are indicating stop, the combination Acomprising, 'a route selector for said through route including a switch selector relay for each switch of said through route, means controlled by trallic conditions on said through route and by operation of the manual control device for the entrance end of the rst of said intermediate routes for energizing rsaid route selector only if said through route is unoccupied, means controlled by said route selector in its energized condition and by operation of the manual control device for the exit Vend of the last of said intermediate routes for arranging all the switches of said intermediate routes in the position required for said through route and for clearing said throughY traic signal only if said through route is unoccupied, and means controlled by one operation of the manual control device for the entrance end of the first of said intermediate routes and of the manual control device for the exit end of the last of said intermediate routes and controlled by two operations of each of the other manual control devices for said intermediate routes for arranging the switches in the position required for said through route and clearing a signal for each of said intermediate routes while said through traffic signal indicates stop.

13. In interlocking control apparatus including a manual control device for each route end of a plurality of interconnected railway track routes, including a preliminary route selector and a nal route selector and also a main exit stick relay for each route, the combination comprising, means controlled by operation of the manual control device ofthe entrance end of the rst of a plurality the preliminary route selector for said first' route,

an auxiliary exit stick relay and an intermediate route stick relay for each of said plurality of successive routes except the last one, means controlled by energization of the preliminary route selector for each route for energizing the auxiliary exit stick relay for its route if its main exit stick relay is deenergized, means controlled by operation of the manual control device for the exit end of each route for energizing the main exit stick relay for the same route if its preliminary route selector' is energized, means controlled by a second operation of the manual -control device for the exit end of each route and by the auxiliary exit stick relay for the same route for energizing the intermediate route stick relay for its route if the auxiliary exit stick relay for the same route is deenergized, means controlled by energization of each intermediate route stick relay for energizing the preliminary route selector for the next route, means controlled by energization of each main exit stick relay for energizing the final route selector for its route, means controlled by the pre- I liminary and nal route selectors independently of the main exit stick relays for eiecting operation of the switches to the positions required by said routes for each direction of trailic movements and means controlled by the main exit stick relays for effecting the clearing of the signals for said routes. Y

14. In interlocking control apparatus including a manual control device for each route end vof a plurality of interconnected railway track routes, in Which a through trafllc signal is provided for governing traffic movements over a through route including a plurality of intermediate routes in series While the signals for said intermediate routes are indicating stop, and including a pre- 18 liminary route selector and a final routeselector and also a main exit stick relay for each of said intermediate routes, the combinationy vcomprising, an auxiliary exit stick relay and an intermediate route stick relay for each of said intermediate routes except the last one in saidseries, means controlled by operation of the manual control device for the entrance end of said rst intermediate route for energizing the preliminary route `selector for said rst intermediate route, means controlled by the preliminary route selector for each intermediate route independently of the manual control device for the exit end of the same intermediate route for energizing the auxiliary exit stick relay for its intermediate route if its main exit stick relay is deenergized, means controlled by operation of the manual controldevice for the exit end of each route for energizing its main exit stick relay if its preliminary route selector is energized, means controlled by a second operation of the manual control device for ythe exit end of each intermediate route except the last one for energizing its intermediate route stick relay, means controlled by each intermediate route stick relay for energizing the preliminary route selector for the next succeeding route, means controlled by each exit stick relay for energizing the nal route selector for operating the switches and clearing the signal for its route, and means controlled by operation of only the manual control device for the entrance end of the lirst route and the manual control device for the exit end of the last route for eiecting energization of the preliminary and final route selectors for arranging said through route and clearing said through traiiic signal.

15. In interlocking control apparatus for a plurality of railway track routes including a, first and a second route arranged end to end with the exit end of therst route adjoining the entrance end of the second route, including a lirst manual control device for the entrance end of said first route and a second manual control device for the exit end of said rst route and the entrance end of said second route and also a third manual control device for the exit end of said second route', including a preliminary route selector relay and a iinal route selector relay for each of said routes, the combination comprising, a main exit stick relay and an auxiliary exit stick relay and also an intermediate route stick relay for said rst route, means controlled by'operation of said first manual control device for energizing the preliminary route selector relay for said rst route, means controlled by energization of said preliminary route selector relay for said first route independently of the manual control device for the exit end of said first route for energizing said auxiliary exit stick relay if said main exit stick relay is deenergized, means 'controlled by operation of said second manual control'device for energizing said main exit stick relay if said preliminary route selector relay for said rst route is energized, means controlled by a second operation of said second manual control device and by the auX- iliary exit stick relay for the same route for energizing said intermediate route stick relay if said auxliary exit stick relay is deenergized, means controlled by said intermediate route stick relay for energizing said preliminary route selector relay for said second route, and means controlled by operation ofv said third manual control device While the preliminary route selector relay for said second route is energized for energizing the final route selector relays for said iirst and second 19 routes for arranging the switches and clearing the signals for said routes.

16.In interlocking control apparatus including a manual control device for each route end of a plurality of interconnected railway track routes, in which a through traiic signal is provided for governing traiiic movements over a through route including a plurality of intermediate routes in series While the signals for said intermediate routes are indicating stop, the combination comprising, a main exit stick relay for each of said intermediate routes, an auxiliary exit stick `relay and an intermediate route stick relay for each of said intermediate routes except the last one, means controlled by operation of the manual control device for the entrance end of each of said intermediate routes except the last one for energizing its auxiliary exit stick re lay if its main exit stick relay is deenergized, means controlled Vby operation of the manual control device for the exit end after operation of the manual control device for the entrance end of each of said intermediate routes for energizing its main exit stick relay, means controlled by asecond operation of the manual control device for the exit end of each of said intermediate routes except the last one and by the auxiliary exit stick relay for the same route for energizing its intermediate route stick relay if its auxiliary exit stick relay is deenergized, means controlled by said intermediate route stick relays and by said main exit stick relays for clearing signals for said intermediate routes, and means controlledl by operation of only the manualV control device for the entrance end of the iirst route of said series and the manual control device for the exit end of the last route of said series for clearing said through traiiic signal.

17. In interlocking control apparatus for a pliuality of railway track routes including a rst and a second route arranged end to end with the eXit end of the rst route adjoining the entrance end of the second route, including a nrst manual control device for the entrance end of said first route and a second manual control device for the eXit end of said first route and the entrance end of said second route and also a third manual control device for the exit end of said second route, the combination comprising, a main exit stick relay and an auxiliary exit stick relay and also an intermediate route stick relay for said iirst route, an exit stick relay for said second route, means controlled by operation of said first manual control device independently of said second manual control device for energizing said auxiliary exit stick relay, means controlled by operation of said second manual control device after operation of said iirst manual control device for energizing said main exit stick relay, means controlled by said auxiliary exit stick relay and by a second operation of said second manual control device for energizing said intermediate route stick relay if said auxiliary exit stick relay is deenergized, means controlled by a front contact of said intermediate route stick relay and by operation of said third manual control device for energizing said exit stick relay for said second route, a signal for said iirst route controlled by a front contact of said main .2.0 exit stick relay, and a second signal for said second route controlled by said intermediate route stick relay and by the exit stick relay for said second route.

18. In interlocking control apparatus for a plurality of railway track routes including a first and a second route arranged end to end with the exit end of the rst route adjoining the entrance end of the second route, including a iirst manual control device for the entrance end of said i'lrst route and a second manual control device ior the exit end of said first route and the entrance end of said second route and also a third manual control device for the exit end of said second route, including a iirst and a second signal for governing traino movements in a given direction over said iirst and second routes resnectively, including a through trafc signal for governing traffic movements in said given direction over both of said routes while said iirst and second signals indicate stop, the combination comprising, a through-route control relay, a main exit stick relay and an auxiliary exit stick relay and also an intermediate route stick relay for said rst route, an exit stick relay for said second route, means controlled by operation of said rst manual control device independently of said second manual control device for energizing said auxiliary exit stick relay, means controlled by operation of said second manual control device after operation of said iirst manual control device for energizing said :nain exit stick relay, means controlled by said auxiliary exit stick relay and by a second operation of said second manual control device for` energizing said intermediate route stick relay if said auxiliary exit stick relay is deenergized, means controlled by a front contact of said intermediate route stick relay and by operation of said third manual control device for energizing said exit stick relay for said second route, means controlled by a front Contact of said main exit stick relay for controlling said iirst signal, means controlled by a. front contact of said intermediate route stick relay and by a front contact of said exit stick relay for said second route for controlling said second signal, means controlled by operation of said rst manual control device While said main exit stick relay is deenergized for energizing said through-route control relay, means `controlled by a front contact of said through-route control relay and by operation of said third manual control device for energizing said exit stick relay for said second route, and means controlled by a front contact of said exit stick relay for said second route and by a back contact of said main exit stick relay for controlling said through trafc signal.

RONALD A. MCCANN.

REFERENCES CITED The following references are of record in the nie of this patent:

UNITED sTATEs PATENTS Num'cer Name Date 2,300,272 Young Oct. 27, 1942 '2,301,297 Lewis Nov. 10, 1942 2.315%864, Lewis Apr. 6. 1943 

